DockerCLI/docs/reference/commandline/inspect.md

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inspect

Usage:  docker inspect [OPTIONS] CONTAINER|IMAGE|TASK [CONTAINER|IMAGE|TASK...]

Return low-level information on a container, image or task

  -f, --format       Format the output using the given go template
  --help             Print usage
  -s, --size         Display total file sizes if the type is container
                     values are "image" or "container" or "task
  --type             Return JSON for specified type, (e.g image, container or task)

By default, this will render all results in a JSON array. If the container and image have the same name, this will return container JSON for unspecified type. If a format is specified, the given template will be executed for each result.

Go's text/template package describes all the details of the format.

Examples

Get an instance's IP address:

For the most part, you can pick out any field from the JSON in a fairly straightforward manner.

$ docker inspect --format='{{range .NetworkSettings.Networks}}{{.IPAddress}}{{end}}' $INSTANCE_ID

Get an instance's MAC address:

For the most part, you can pick out any field from the JSON in a fairly straightforward manner.

$ docker inspect --format='{{range .NetworkSettings.Networks}}{{.MacAddress}}{{end}}' $INSTANCE_ID

Get an instance's log path:

$ docker inspect --format='{{.LogPath}}' $INSTANCE_ID

Get a Task's image name:

$ docker inspect --format='{{.Container.Spec.Image}}' $INSTANCE_ID

List all port bindings:

One can loop over arrays and maps in the results to produce simple text output:

$ docker inspect --format='{{range $p, $conf := .NetworkSettings.Ports}} {{$p}} -> {{(index $conf 0).HostPort}} {{end}}' $INSTANCE_ID

Find a specific port mapping:

The .Field syntax doesn't work when the field name begins with a number, but the template language's index function does. The .NetworkSettings.Ports section contains a map of the internal port mappings to a list of external address/port objects. To grab just the numeric public port, you use index to find the specific port map, and then index 0 contains the first object inside of that. Then we ask for the HostPort field to get the public address.

$ docker inspect --format='{{(index (index .NetworkSettings.Ports "8787/tcp") 0).HostPort}}' $INSTANCE_ID

Get a subsection in JSON format:

If you request a field which is itself a structure containing other fields, by default you get a Go-style dump of the inner values. Docker adds a template function, json, which can be applied to get results in JSON format.

$ docker inspect --format='{{json .Config}}' $INSTANCE_ID